Department of Pediatrics, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Pediatr Neonatol. 2011 Feb;52(1):18-23. doi: 10.1016/j.pedneo.2010.12.011. Epub 2011 Feb 23.
Inhaled β(2)-adrenergic receptor (β(2)-AR) agonists are the mainstay of treatment of acute asthma. Polymorphisms of the β(2)-AR, especially codons 16, 27, and 164, may affect the functions of the receptor. This study was conducted to investigate whether different polymorphisms of the β(2)-AR are related to the treatment responses of an inhaled β(2)-AR agonist in children with nocturnal and nonnocturnal asthma in Taiwan.
The nocturnal asthma group consisted of 27 children (mean age of 10.3±2.4 years), and the nonnocturnal asthma group consisted of 24 patients (mean age of 9.9±3.0 years). Allele-specific polymerase chain reaction was performed to determine 16, 27, and 164 loci alleles of β(2)-AR genetic polymorphisms, and peak expiratory flow (PEF) was measured before and 1 hour after inhalation of 0.2mg/kg/dose of terbutaline to determine the treatment response in these patients.
The polymorphisms of β(2)-AR 27 but not 16 or 164 were significantly associated with the response to terbutaline nebulizer (p<0.05). The polymorphism of β(2)-AR 16 was associated with nocturnal asthma (p=0.027). The Gly16 allele was more prevalent in the nocturnal asthma group (9/27; 33.3%) than in the nonnocturnal asthma group (3/24; 12.5%). Arg16 allele was less prevalent in the nocturnal asthma (3/27; 11.1%) than in the nonnocturnal asthma group (10/24; 41.7%). There was also a linkage disequilibrium found between β(2)-AR 16 (Arg/Arg) and β(2)-AR 27 (Gln/Gln).
These findings suggest that polymorphisms of β(2)-AR 16 are related to nocturnal asthma and polymorphisms of β(2)-AR 27 are associated with the variable responses to the inhaled terbutaline in children with nocturnal and nonnocturnal asthma.
吸入性β(2)-肾上腺素受体（β(2)-AR）激动剂是治疗急性哮喘的主要方法。β(2)-AR 的多态性，特别是密码子 16、27 和 164，可能影响受体的功能。本研究旨在探讨β(2)-AR 的不同多态性是否与台湾地区儿童夜间和非夜间哮喘患者吸入β(2)-AR 激动剂的治疗反应有关。
夜间哮喘组由 27 名儿童（平均年龄 10.3±2.4 岁）组成，非夜间哮喘组由 24 名患者（平均年龄 9.9±3.0 岁）组成。采用等位基因特异性聚合酶链反应检测β(2)-AR 遗传多态性的 16、27 和 164 位等位基因，吸入 0.2mg/kg/剂量特布他林后 1 小时测量呼气峰流速（PEF），以确定这些患者的治疗反应。
β(2)-AR27 但不是 16 或 164 的多态性与特布他林雾化器的反应显著相关（p<0.05）。β(2)-AR16 的多态性与夜间哮喘有关（p=0.027）。Gly16 等位基因在夜间哮喘组（9/27；33.3%）中比非夜间哮喘组（3/24；12.5%）更常见。Arg16 等位基因在夜间哮喘组（3/27；11.1%）中比非夜间哮喘组（10/24；41.7%）更少见。还发现β(2)-AR16（Arg/Arg）和β(2)-AR27（Gln/Gln）之间存在连锁不平衡。
这些发现表明，β(2)-AR16 的多态性与夜间哮喘有关，β(2)-AR27 的多态性与夜间和非夜间哮喘儿童吸入特布他林的可变反应有关。
